Juno crossed a gravitational boundary between Jupiter and the sun, and the gas giant began pulling the spacecraft in ahead of a planned July 4 arrival, NASA officials said.
"For the rest of the mission, we project Jupiter's gravity will dominate as the trajectory-perturbing effects by other celestial bodies are reduced to insignificant roles," Juno project manager Rick Nybakken, of NASA's Jet Propulsion Laboratory in Pasadena, California, said in a statement.
Juno spacecraft was launched on 5th August, 2011 from Cape Canaveral Air Force Station.Since then, three gravitational forces have markedly influenced the spacecraft's trek — those of the sun, the Earth and Jupiter. At the beginning stages of Juno's trip, Earth was most influential; more recently, the sun has had the biggest impact on the spacecraft's trajectory, NASA officials said.
Juno will search for the clues about how the planet formed, whether it has a rocky core, the amount of water present in its deeper layers, how its mass is distributed and its deep winds which can reach speeds of 618 km/h. Juno will be the second spacecraft to orbit Jupiter after the Galileo probe which orbited from 1995 to 2003.